Page:NIOSH Manual of Analytical Methods - 9002.pdf/2

This page needs to be proofread.

ASBESTOS (bulk): METHOD 9002, Issue 2, dated 15 August 1994 - Page 2 of 9 REAGENTS:

EQUIPMENT:

1. Refractive index (RI) liquids for Dispersion Staining: high-dispersion (HD) series, 1.550, 1.605, 1.620. 2. Refractive index liquids: 1.670, 1.680, and 1.700. 3. Asbestos reference samples such as SRM

  1. 1866, available from the National Institute of

Standards and Technology.* 4. Distilled Water (optional). 5. Concentrated HCl: ACS reagent grade.

1. Sample containers: screw-top plastic vials of 10- to 50-mL capacity. 2. Microscope, polarized light, with polarizer, analyzer, port for retardation plate, 360E graduated rotating stage, substage condenser with iris, lamp, lamp iris, and: a. Objective lenses: 10X, 20X, and 40X or near equivalent. b. Ocular lense: 10X minimum. c. Eyepiece reticle: crosshair. d. Dispersion staining objective lens or equivalent. e. Compensator plate: ca. 550 nm± 20 nm, retardation: "first order red" compensator. 3. Microscope slides: 75 mm x 25 mm. 4. Cover slips. 5. Ventilated hood or negative-pressure glove box. 6. Mortar and pestle: agate or porcelain. 7. Stereomicroscope, ca. 10 to 45X. 8. Light source: incandescent or fluorescent. 9. Tweezers, dissecting needles, spatulas, probes, and scalpels. 10. Glassine paper or clean glass plate. 11. Low-speed hand drill with coarse burr bit (optional).

  • See SPECIAL PRECAUTIONS

SPECIAL PRECAUTIONS: Asbestos, a human carcinogen, should be handled only in an exhaust hood (equipped with a HEPA filter) [2]. Precautions should be taken when collecting unknown samples, which may be asbestos, to preclude exposure to the person collecting the sample and minimize the disruption to the parent material [3]. Disposal of asbestos-containing materials should follow EPA Guidelines [4].

SAMPLING: 1. Place 1 to 10 g of the material to be analyzed in a sample container. NOTE: For large samples (i.e., whole ceiling tiles) that are fairly homogenous, a representative small portion should be submitted for analysis. Sample size should be adjusted to ensure that it is representative of the parent material. 2. Make sure that sample containers are taped so they will not open in transit. 3. Ship the samples in a rigid container with sufficient packing material to prevent damage or sample loss. SAMPLE PREPARATION: 4. Visually examine samples in the container and with a low-magnification stereomicroscope in a hood. (If necessary, a sample may be carefully removed from the container and placed on glassine transfer paper or clean glass plate for examination). Break off a portion of the sample and examine the edges for emergent fibers. Note the homogeneity of the sample. Some hard tiles can be broken, and the edges examined for emergent fibers. If fibers are found, make an estimate of the amount and type of fibers present, confirm fiber type (step 14) and quantify (step 15). 5. In a hood, open sample container and with tweezers remove small, representative portions of the sample. 1. If there are obvious separable layers, sample and analyze each layer separately. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94

This article is issued from Wikisource. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.